Francis greene



AFRANCIS GREENE, o-F TROY, PENNSYLVANIA.

Letters Patent No. F119,466, (lated June 30, 1868.

IMPROVEMENT IN .DOOR-KEYS.

dige rehulefreftrteh tu in these tstters @mit rmt mating part ni thesmue.

To ALL -WiioM 1T MAY ooNeEnN:

Bc it kno'wn that I, FRANOIS GREENE, of Troy, in the county of Bradford,and State o f Pennsylvania, have invented a new and 'useful Improvementiii-Keys; and I do hereby declare that the following is a full, clear,and exact description thereof, reference being had tothe accompanyingdrawings.

The natureof my invention consists in forminga guard to the key, in sucha, manner as that when it is in the lock on the inside of the door, itcannot be turned by any instrument in the hand of a person outside.

Toy enable others skilled inthe art to which it appertains to 'makeanduse my invention, I describe it as follows, viz:

I make the'stem, A, of the key without`t-he wing a, thestem being madein the ordinary way, except thet at the end it is turned down, to form.a smell round teno'nl, as seen at h, iig. 3, and a small groove isturned in said stem, as seenlat d, iig, 3. rlhis groove may be aboutone-eighth or three-sixteenths of an inchv long, and aboutone-thirty`seeond of an inch deep. In this groove I pince e. thin stripot' suitable metal, bending it arbund in the groove, vso as to form a.cylindrical ring, it being cnt ofthe proper length to allow its ends tomeet when in the groove, and its .exterior surface to be even withthecorresponding surface ofthe stem, as seen at n, Figure 5, and beingsogmadc as to allow it to revolve in said groove. -I then form the guardC, as shown :xt Figure'll, with a hole at e, just large enough to slipover the end ofthe stem A, and fit neatly on the ring in the groove justdescribed, and in the nrxn or part f of the guardI make a hole, largeenough'to work neatly `and freely on the tenon h, Figure 3. I thenenlarge this hole for about two-thirds of the distance through the armf, as seen ings. 4 and 5. When thisguard is placed on the stern A of thekey, its arm epnsses on to the cylindrical ring in the grooved, g. 5,:of the stem, and the arnif on to the tenon tjat the end of th'e saidstem, this tenon being of "such alength as to pass a shortdistance'through the small partei' the hole in the arm f, so that it canbe riveted on the shoulder of said, hole, so'as to prevent it fromcoming of?, and yet so as to allow it to reiolve freely thereon,(see'fig. 5 at i.) i The arm e, I solder to the ring'n in the groove d.i I then neatly plug up the outer end of the hole'in the arm f, so as15o-conceal the riveting of the tenon L, and to make a good finish totlestem A. "I then make the wing a of the shape and size desired, andsolderv it tothe stem AA, as seen in Figures fi and 2. The arms-e andfof the guard AG are of such a length as to allow the party of the sameto just freely pass over the extreme edge of the wing a, leaving nomorespace between them than is necessary to allow themtdpn's'sifreely. i v vIt will be seen from theforegoing description, that 'irhen the key ismadewiththe guard, as described, and is introduced intthe key-hole ofits appropriate lock, it will turn therein freely, while the guard isstationary; and if a burglar tries to turn thekey by means of nippers,or-any kind of tool he may have' t'o operate with from the outside, hewill {indhirnself defeated in the attempt, the guard being incapable ofturning while in the lock; :1nd if the precaution is teken, when lockingthe door', to` so turn the key. as that its vfing a will not Y coincidein position with the guard C, then it cannot be forced out ofthe lock,and the burglar cannot introduce a key or lock-pick from-the outside. i

' Havingthus fully described my invention,.\vhnt I claim as new, anddesire to secureby Letters Patent, is- The gunrd C',incoxnbination withthe armf, for closing the key-hole, constructed and attached to the key,substantially las shown ond-described, und for the purpose specified.y i

FRANCIS GREENE.

Witnesses:

-W. H. CAnNoenAN, D. A-. LAMENT.

